In the prior art, there are numerous alarm systems which are installed in connection with houses and other structure for alerting residents or security personnel to a threat to the house or the individuals therein. For example, alarm systems are known which generate loud noises when a door is opened without authorization or a window is broken, and/or which notify security personnel of such conditions to enable such personnel to respond to the house.
Some patents and patent publications that describe such security systems include: U.S. Pat. Nos. 4,697,077 (Yuasa et al.), 5,283,551 (Guscott), 5,576,972 (Harrison), 5,825,412 (Hobson et al.), 5,937,092 (Wootton et al.), 6,069,655 (Seeley et al.), 6,400,265 (Saylor et al.), German Patent Publication No. DE 10122294, International Patent Publication No. WO 98/28706 (WO '706) and Japanese Patent No. JP2004077350 (JP '350).
Guscott describes an intrusion alarm system including a triggering sensor and a linear array of sensors triggered to sample an area of interest when activated by the triggering sensor. Differences in the sample infrared emissions enable a determination of the object as a human or a dog.
Harrison describes a monitoring system including various sensors, one of which is an optical sensor, and data from all of the sensors is directed to a neural network computer which analyzes the data and detects and identifies the objects in the sensed area which may be people, animals or objects.
Hobson et al. describes a video detection system for monitoring railroad crossings wherein a camera views the railroad crossing and establishes the presence of objects and the size thereof. An alarm is sounded based on the size of the object.
Wootton et al. describes a security system in which images of a detection area are sensed and compared with previously obtained images to determine the presence and movement of an intruder in the detection area. In this regard, reference is made to Yuasa et al. which is said to describe use of a frame subtraction technique to derive the presence of an object and conveyance of this information to a remote location for viewing by a human.
Seeley et al. describes a security system in which video cameras send images from a site control unit (SCU) to a central station which may be remote from the SCU. Video signals from the cameras are directed to an image processor section which determines the presence of an intruder and classifies the intruder.
Saylor et al. describes a security system wherein images obtained from a security camera are transmitted over the Internet to be seen on a computer. Other ways to be informed of the existence of an alarm condition are also mentioned.
German Patent Publication No. DE 10122294 describes an alarm system which undertakes different actions based on detection of an animal in a detection area.
WO '706 describes a video detection system in which different objects are recognized by comparing a set of shape features (e.g., an outline), derived from comparison of an instantaneously obtained image to previously obtained images, to sets of features of humans and animals.
JP '350 describes a technique for determining whether an object is a human by comparing the silhouette of the object to previously registered silhouette information.